Here are a couple of pics of the new exhaust setup. The header is an OPM 4-1 and the exhaust includes a 2.5" collector, tube, and Magnaflow resonator with a 2.5" turn-down. On top is the old setup. The new setup weighs in at 25 lbs with everything you see pictured (header included). The old setup was just a hair under 35 lbs. I'm guessing 9 of those lbs came from the OPM header vs. the OEM cast header. From the header back, both exhaust setups seem pretty similar in weight but the quality of the Magnaflow resonator is much better than the cheap cherry bombs I had before. I hope the noise is similar since the old setup was actually pretty quiet (in a super loud sort of way). I used the OEM hanger setup under the resonator and I just need to pick up a set of longer hangers to do the job.



Here's a shot of the "quick release" collector designed to tear away from the header without bringing the whole motor with it.



Here's a shot of the fit under the pan. It's pretty close all around, and about as good as you can expect from a 4-1. I had to remove the front crossmember to get the header in and as you can see it is a very tight fit in the front as well. I had every finger and toe crossed when I put the crossmember back in because I was SURE it wasn't going to fit.




My only complaint is that the resonator is going to be very close to the ground when all is said and done. I'm going to try it like this, but I'm going to order a flex joint to install between the header and resonator so that I can tuck it up a little higher and so that the exhaust acts less like a lever arm on the header (although there is some play in this joint already so there isn't much force on the header).



BTW, I'm using a new picture service, so let me know if you can't see them. Also, I have full size pics for anyone who want's to see them.

 

How tight is the quick-release? I can see it rattling pretty badly if it's not a tight slip fit. Otherwise, I like the idea. Is that your idea?

 

This is really making me chuckle.....I will go take pics now....

 

looks nice! Have you considered using exhaust wrap?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by johng &raquo;</TD></TR><TR><TD CLASS="quote">How tight is the quick-release? I can see it rattling pretty badly if it's not a tight slip fit. Otherwise, I like the idea. Is that your idea?
</TD></TR></TABLE>

I went through tons of springs before I found these. They almost have a progressive feel to them in that you can stretch them with your hands to a point and then it takes a lot more effort to move them more. They are very, very tight and require a vise-grip to remove them. I can't even pull the exhaust tube away from where it butts up to the collector with my hands. I think the only thing that is going to separate these two pieces is a tool or an "off" at the track. As for rattle, they make a very tight seal where the 2.5" ID flair tapers to 2.5" OD, so I don't expect any rattle or leak. I can't take credit for the spring release idea. It is based on ideas I got from CRX Lee and SMSP (thanks guys).

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LX4CYL &raquo;</TD></TR><TR><TD CLASS="quote">looks nice! Have you considered using exhaust wrap?</TD></TR></TABLE>

Where, on the header or the joint? I might do something like that on the joint if I find that it is leaking, but otherwise I'm just going to paint the whole thing to keep it from rusting.

 

no no, I meant to prevent the heat from heating the oil pan and other parts of the car. I remember reading one story of a guy on here how killed their inboard CV boot by sitting at idle too long with a hot exhaust...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LX4CYL &raquo;</TD></TR><TR><TD CLASS="quote">no no, I meant to prevent the heat from heating the oil pan and other parts of the car. I remember reading one story of a guy on here how killed their inboard CV boot by sitting at idle too long with a hot exhaust...</TD></TR></TABLE>

I see. I don't plan to wrap the header at this point unless it becomes an issue later. I'm already melting damn near every boot on the car (recently replaced several) and I doubt that this will make it any worse. We'll see.

 

Since It's still a street car mine has a cat and works very well with a comptech header. I painted the full length in BBQ flat black paint

I used all stainless and it was very mellow almost like a real sports car at idle

 

looks good, cant wait to see how you fair against paul this weekend with your new power!
dan&lt;-who thinks that h1 cars fear h4 crxs

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Looose_R &raquo;</TD></TR><TR><TD CLASS="quote">looks good, cant wait to see how you fair against paul this weekend </TD></TR></TABLE>


In the obnoxiously noisy cagegory I don't stand a chance against Paul

 

Travis,
this setup looks remarkably like mine (minus the spring releases). I can't wait to hear how your car runs since i have the exact same engine, tranny and header/exhaust that you have.
Where would one get a flex-joint that you mentioned? I like the idea.
thanks

EDIT: found one:
http://www.autosupermart.com/shop/pace02937.html
if anyone know of a cheaper option, chime in.

 

support your board sponser and get a much better deal at the same time

http://www.kteller.com/store/i...85_87

 

Regarding header wrapping vs. ceramic coating, go to:

http://www.improvedtouring.com

go to tech talk and you'll see a heading "headers: ceramic coating? Wrapping?"

Lots of good info there plus links to ceramic coating companies.

In a nut shell:

Wrapping - will reduce underhood temps, cheap, will accelerate header corrosion.

Ceramic coating - will reduce underhood temps more, not so cheap (~$160), header will stay intact for much longer.

Cheers, Mark

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LX4CYL &raquo;</TD></TR><TR><TD CLASS="quote">no no, I meant to prevent the heat from heating the oil pan and other parts of the car. I remember reading one story of a guy on here how killed their inboard CV boot by sitting at idle too long with a hot exhaust...</TD></TR></TABLE>

That guy was me, but I have since ditched the header wrap after being verbally abused by our friend metalworker for wrapping his beautiful work with bad old header wrap. And sure enough, after only a couple of months with the wrap around the collector (under the oil pan) when I removed the wrap the collector had already started to show signs of excessive heat and corrosion.

IIRC Walt (metalworker) explained that the wrap causes 2 problems...
1. Moisture. When the car is parked and the wrap gets wet, its like leaving wet rags wrapped around the header. Since the tubing is just plain old steel... Well...
2. Heat. While the wrap is keeping the heat off the oil pan, its keeping it on the collector. What does dissapate does so very slowly. Not good.

So, now I just make sure I never leave the motor running for long periods while the car is sitting still (how the first CV boot got KO'd). When in motion, especially fast motion, the air coming under the car is sufficient to keep eveything cooled off.
Mine is just coated with the high heat paint that was on it when Walt sent it to me. 5 race weekends later it still looks great (except where the header wrap was
).

 

for the record, ive had absolutely no problems with thermotec 'cool it' header wrap on my DC sport mild steel and ceramic coated header on my d16a6. this was through california weather with the winter/rainy season and a season of racing. the wrap was destroyed when lamers tried unsucessfully to remove it when they jacked my car, but i sitll have it and the header is in fine condition.

ive heard bad accounts as well. perhaps i got lucky in the quality of the welds and steel mine happened to be constructed out of. but i would personally do it to my header again.

actually, if you just want to thermally protect the oilpan, then just put one of those reflective patches that are insulated on the oilpan. i think you can get knockoff stuff off ebay too.


Modified by Tyson at 12:19 PM 10/15/2004

 

or go to ebay and find one even (much) cheaper:

http://cgi.ebay.com/ebaymotors...33633

damn I love ebay.

 

Well, in spite of the many other problems I had this weekend, the exhaust was problem free. At very low idle (less than 1K) the springs rattle, but otherwise no problems with the springs. As for the noise, it was much quieter than I anticipated...even quieter than my previous exhaust which had two resonators. Considering that I also changed from the OEM header to a 2.5" 4-1, that's pretty remarkable. to Magnaflow. I don't have an actual dB reading, but considering that my previous setup was right at 100-101 dB, I'm sure this is under 100.

By the way, thanks for the link SJR. That's a good find.

 

now we just need to pound out the damage...except yours is cooler, you got bit by the viper...I got bit by the wall...

You doing Firebird Travis?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PSUCRX &raquo;</TD></TR><TR><TD CLASS="quote">now we just need to pound out the damage...except yours is cooler, you got bit by the viper...I got bit by the wall...

You doing Firebird Travis?</TD></TR></TABLE>

Time for a rubber mallet party I guess.

I couldn't have made Firebird event because of a trip to New Orleans that week, but it looks like the event was cancelled so it doesn't matter anyway. See you at PIR. Isn't it time for you to make a new PIR thread anyway?

 

Nah, we usually start the new thread 2 weeks before the event...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by travis &raquo;</TD></TR><TR><TD CLASS="quote">
As for rattle, they make a very tight seal where the 2.5" ID flair tapers to 2.5" OD, so I don't expect any rattle or leak. I can't take credit for the spring release idea. It is based on ideas I got from CRX Lee and SMSP (thanks guys).
</TD></TR></TABLE>

Actually, I run mine actually as a somewhat loose fit then have the springs pull up the end of the pipe into the flare.

A rattle you say? On a 90+db racecar only on a racetrack, who can hear or cares about a rattle? Not that I have heard nor seen evidence of it. My street car has a traditional flanged and clamped exhaust but the racecars have long been spring mounted. So what if there is a rattle or the least bit of exhaust leak as this is a full out racecar operated mostly at full throttle and at speed? No minor escapage, noise or fume will have any effect on anything however the exhaust is now a break-away system so if you catch it on a berm, ground, etc. when you made an errant excursion, then it jsut nicely shucks off and you don't trash your nice, not inexpensive race header.

 

hi travis-
long time no hear from....looks like opm has your business now....lol
I would suggest you mount the muffler much further forward, my dyno tests resulted in a 5hp gain by mounting it closer to the header flange, but then again, I was using my header not the opm unit.
I ordered an opm unit from walt, bout 7 years ago now...never arrived, so I developed my own..in walts defense, (cause im not here to speak badly of him), he was driving the olds achieva in pscr at the time, and my order just got lost in the mix i think....

I have pics of my set up somewhere....
will have to dig them up for you...
btw- dyno numbers yet???

stay in touch...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Roadracejunkie &raquo;</TD></TR><TR><TD CLASS="quote">
I ordered an opm unit from walt, bout 7 years ago now...never arrived, so I developed my own..in walts defense, (cause im not here to speak badly of him), he was driving the olds achieva in pscr at the time, and my order just got lost in the mix i think....
</TD></TR></TABLE>

Roadracejunkie,
I have no doubt that I have screwed up some orders, but are you sure that you were dealing with me. How did I take your order? I did do some pro racing in World Challenge, Super Touring and whatever the left overs of IMSA were calling themselves at the time, but during this time I was depending on companies like OPM and was not selling anything direct. I guess the main thing is that I'm worried that I took your order and your money and didn't send you your product. Since you sell to racers, I hope that you would understand that we really don't consider an order an order without some kind of deposit or confirmation that they really want the product and aren't just kicking ideas around.

 

Walt-
I ordered the header from you in the paddock at road atlanta in 1996 when Rick Dishaw an I won the ITA championship. Tom Fowler was pitching his (yours) header at the time we were there.
The order was presented as a "loosely" discussed topic like you suggested. I saw you at the pscr race in 1997 at road atlanta when I was running with a factory honda del sol team, and I saw you and brought it up, and I believe you said you were backed up for a few weeks. I never heard another word, a deposit was never taken, so relax, you don't owe me anything, I am honest .
I just never followed up after that pro race with you, and you didn't contact me to elaborate on the production date or completion, so no harm done really.
I know your headers are good, guys up here in Ohio have them, and they like them.
I have my own design that I developed and dyno tested over the last couple years, that is making 7 hp over the DC 4-1...so not a bad design I would say.

Nice to hear from you and that you care about this since it is so many years past.
I do my best to not forget any of my customers ideas, orders, or deposits either.

 

Travis- congrats on finally getting a new header, heh... I still need to do a back-to-back dyno comparison of my old OPM vs. SMSP, but the butt-dyno tells me all sorts of good things (and makes me feel all tingly)

plus I don't think I ever posted pics:



(and the OPM had header wrap on it before I purchased it)